Glomeruli isolated from normal and diabetic kidneys are used for purification of glomerular basement membrane with techniques that preserve architectural and molecular integrity. The overall objectives of this project are to: a) purify and characterize the authentic components of normal and diabetic glomerular basement membrane; b) determine the nature and extracellular fate of the first formed units of these components; c) compare their biosynthesis and degradation in normal and diabetic preparations using both in vitro and in vivo approaches; and d) examine the manner in which diabetes alters structural or functional properties of glomerular basement membrane proteins.